I just saw the new Wolverine PF and I think it's a redesign done right. Personally I would've made the gloves longer, but I like the interpretation overall. The iconic tiger stripes are there, and the boots was modernized yet it carries the silhouette of the classic boots with wide fins on the legs. Pair those things with very good sculpt and pose, and it would tempt even some of the purists. And IMO, that new Wolverine PF is well-sculpted. Great anatomy, generic pose maybe but works for the character, and IMO the best 1/4 portrait of Logan so far, particularly the masked. Another modernized SSC interpretation I liked is their new Thanos.
Personally, my nitpicks on the Legendary Scale Batman are the bright-colored belt (easy fix), and the shoe laces. I like the idea of shin guard over boots similar to the Arkham Asylum/City suit -- I think SSC even got the better shin guards as they are shaped like Batman's comic boots with pointed tips -- but the shoe laces for me don't look good. Pose could have been much better as well, same with the base.
As for Deathstroke, if Sideshow worried that some people might find the pirate boots corny for 2017, they could have used armors or gaiters that would create the same silhouette as a pirate boot's upper, like how it was done for modern Captain America. No switch-out arms with gun/rifle? Perhaps a more imposing physique (let's cut the "Deathstroke moves fast so he should be more athletic!" excuse since these characters are from comics anyway LOL)? No bandolier.
I think it's not modernization/interpretation per se that's the problem. It's how it's done. Add lines and details here and there maybe, but make sure they look good and not just added for detail's sake, and retain the iconic shapes and silhouettes. Then make sure the sculpt and pose would complement those creative liberties taken